Year	Percent
1983	3.2
1984	2.63
1985	2.96
1986	2.64
1987	2.47
1988	2
1989	1.59
1990	1.61
1991	1.48
1992	2.03
1993	2.33
1994	3.48
1995	2.92
1996	3.29
1997	2.53
1998	2.76
1999	2.39
2000	2.35
2001	1.81
2002	2.62
2003	3.68
2004	5.11
2005	4.49
2006	4.73
2007	4.07
2008	5.06
2009	5.12
2010	4.36
2011	4.9
2012	5.14
2013	5.85
2014	5.85
2015	6.67
2016	6.29
2017	5.52
2018	5.59
2019	5.59
2020	6.77